treemap.js

/* 
 * If running inside bl.ocks.org we want to resize the iframe to fit both graphs
 * This bit of code was shared originally at https://gist.github.com/benjchristensen/2657838
 */
if(parent.document.getElementsByTagName("iframe")[0]) {
	parent.document.getElementsByTagName("iframe")[0].setAttribute('style', 'height: 700px !important');
}

var margin = {top: 20, right: 0, bottom: 0, left: 0},
    width = 820,
    height = 700 - margin.top - margin.bottom,
    formatNumber = d3.format(".2s"),
    transitioning;

/* create x and y scales */
var x = d3.scale.linear()
	.domain([0, width])
	.range([0, width]);

var y = d3.scale.linear()
	.domain([0, height])
	.range([0, height]);

var treemap = d3.layout.treemap()
	.children(function(d, depth) { return depth ? null : d.children; })
	.sort(function(a, b) { return a.value - b.value; })
	.ratio(height / width * 0.5 * (1 + Math.sqrt(5)))
	.round(false);

	/* create svg */
var svg = d3.select("#chart").append("svg")
	.attr("width", width + margin.left + margin.right)
	.attr("height", height + margin.bottom + margin.top)
	.style("margin-left", -margin.left + "px")
	.style("margin.right", -margin.right + "px")
	.append("g")
	.attr("transform", "translate(" + margin.left + "," + margin.top + ")")
	.style("shape-rendering", "crispEdges");

var color = d3.scale.category20c();

var grandparent = svg.append("g")
	.attr("class", "grandparent");

grandparent.append("rect")
	.attr("y", -margin.top)
	.attr("width", width)
	.attr("height", margin.top);

grandparent.append("text")
	.attr("x", 6)
	.attr("y", 6 - margin.top)
	.attr("dy", ".75em");

function initialize(root) {
	root.x = root.y = 0;
	root.dx = width;
	root.dy = height;
	root.depth = 0;
}

// Aggregate the values for internal nodes. This is normally done by the
// treemap layout, but not here because of the custom implementation.
function accumulate(d) {
	return d.children
	? d.value = d.children.reduce(function(p, v) { return p + accumulate(v); }, 0)
	: d.value;
}

// Compute the treemap layout recursively such that each group of siblings
// uses the same size (1×1) rather than the dimensions of the parent cell.
// This optimizes the layout for the current zoom state. Note that a wrapper
// object is created for the parent node for each group of siblings so that
// the parent’s dimensions are not discarded as we recurse. Since each group
// of sibling was laid out in 1×1, we must rescale to fit using absolute
// coordinates. This lets us use a viewport to zoom.
function layout(d) {
	if (d.children) {
		treemap.nodes({children: d.children});
		d.children.forEach(function(c) {
			c.x = d.x + c.x * d.dx;
			c.y = d.y + c.y * d.dy;
			c.dx *= d.dx;
			c.dy *= d.dy;
			c.parent = d;
			layout(c);
		});
	}
}

/* display shows the treemap and writes the embedded transition function */
function display(d) {
/* create grandparent bar at top */
	grandparent
		.datum(d.parent)
		.on("click", transition)
		.select("text")
		.text(name(d));

	var g1 = svg.insert("g", ".grandparent")
		.datum(d)
		.attr("class", "depth");
		/* add in data */
	var g = g1.selectAll("g")
		.data(d.children)
		.enter().append("g");
		/* transition on child click */
	g.filter(function(d) { return d.children; })
		.classed("children", true)
		.on("click", transition);
		/* write children rectangles */
	g.selectAll(".child")
		.data(function(d) { return d.children || [d]; })
		.enter().append("rect")
		.attr("class", "child")
		.call(rect)
		.append("title")
		.text(function(d) { return d.name + " " + formatNumber(d.size); });

	/* write parent rectangle */
	g.append("rect")
		.attr("class", "parent")
		.call(rect)
		/* open new window based on the json's URL value for leaf nodes */
		/* Chrome displays this on top */
		.on("click", function(d) { 
			if(!d.children){
				window.open(d.url); 
			}
		})
		.append("title")
		.text(function(d) { return d.name + " " + formatNumber(d.size); }); /*should be d.value*/

	/* Adding a foreign object instead of a text object, allows for text wrapping */
	g.append("foreignObject")
		.call(rect)
		/* open new window based on the json's URL value for leaf nodes */
		/* Firefox displays this on top */
		.on("click", function(d) { 
			if(!d.children){
				window.open(d.url); 
			}
		})
		.attr("class","foreignobj")
		.append("xhtml:div") 
		.attr("dy", ".75em")
		.html(function(d) { 
			if (d.size) {
				return d.name + " (" + formatNumber(d.size) + ")"; 
			} 
			if (d.value > 0 && typeof(d.value) !== "undefined") {
				return d.name + " (" + formatNumber(d.value) + ")"; 
			}
			return d.name;
		})
		.attr("class","textdiv"); //textdiv class allows us to style the text easily with CSS
			/* create transition function for transitions */
	function transition(d) {
		if (transitioning || !d) return;
		transitioning = true;
		var g2 = display(d),
		    t1 = g1.transition().duration(750),
		    t2 = g2.transition().duration(750);
			// Update the domain only after entering new elements.
		x.domain([d.x, d.x + d.dx]);
		y.domain([d.y, d.y + d.dy]);
			// Enable anti-aliasing during the transition.
		svg.style("shape-rendering", null);

		// Draw child nodes on top of parent nodes.
		svg.selectAll(".depth").sort(function(a, b) { return a.depth - b.depth; });
		// Fade-in entering text.
		g2.selectAll("text").style("fill-opacity", 0);
		g2.selectAll("foreignObject div").style("display", "none"); /*added*/

		// Transition to the new view.
		t1.selectAll("text").call(text).style("fill-opacity", 0);
		t2.selectAll("text").call(text).style("fill-opacity", 1);
		t1.selectAll("rect").call(rect);
		t2.selectAll("rect").call(rect);

		t1.selectAll(".textdiv").style("display", "none"); /* added */
		t1.selectAll(".foreignobj").call(foreign); /* added */
		t2.selectAll(".textdiv").style("display", "block"); /* added */
		t2.selectAll(".foreignobj").call(foreign); /* added */ 

		// Remove the old node when the transition is finished.
		t1.remove().each("end", function() {
			svg.style("shape-rendering", "crispEdges");
			transitioning = false;
		});

	}//endfunc transition

	return g;
}//endfunc display

function text(text) {
	text.attr("x", function(d) { return x(d.x) + 6; })
	    .attr("y", function(d) { return y(d.y) + 6; });
}

function rect(rect) {
	rect.attr("x", function(d) { return x(d.x); })
 		.attr("y", function(d) { return y(d.y); })
		.attr("width", function(d) { return x(d.x + d.dx) - x(d.x); })
		.attr("height", function(d) { return y(d.y + d.dy) - y(d.y); })
		.style("background", function(d) { return d.parent ? color(d.name) : null; });
}

function foreign(foreign){ /* added */
	foreign.attr("x", function(d) { return x(d.x); })
		.attr("y", function(d) { return y(d.y); })
		.attr("width", function(d) { return x(d.x + d.dx) - x(d.x); })
		.attr("height", function(d) { return y(d.y + d.dy) - y(d.y); });
}

function name(d) {
	return d.parent ? name(d.parent) + "." + d.name : d.name;
}

function loadJSONFile(file) {
	/* load in data, display root */
	d3.json(file, function(root) {
		loadData(root);
	});
}

function loadData(root) {
	initialize(root);
	accumulate(root);
	layout(root);
	display(root);
}